User guide

Glossary
154 Trimble M3 Total Station User Guide
backsight
Point with known coordinates or known azimuth from the instrument point that
is used to orient the instrument during station setup.
baseline
The position of a point relative to another point.
baud
Used to describe serial communications data transfer speed from one binary
digital device to another. Baud rate is generally one bit per second.
bearing
The angular value defining the direction of a line, based on the local datum used in
the survey.
benchmark point
A survey mark made on a monument having a known location and elevation,
serving as a reference point for surveying.
bubble level
See circular level.
calibrate (equipment)
Adjustments made to the incoming raw decoded data values. For example,
applying an orientation correction to the heading data
calibrate (local site
adjustment)
A method of calculating local site coordinates based on ECEF Cartesian
coordinates.
checksum
A method for checking the integrity of transmitted data. A checksum is an integer
value computed from the data string.
circular level
A spirit level with the inside surface of its upper part ground spherical to form a
circular bubble, and with graduations consisting of concentric circles, for
application where high precision is not required.
compensator
A sensor mounted on the alidade aligned with the horizontal axis and the sighting
axis internally. It detects the angular error and returns to the system to make
necessary corrections.
component
One of the three surveying observations used to define a three-dimensional
baseline between two control points. The same baseline can be defined by
azimuth, delta height, and distance (in ellipsoid coordinates); by delta X, delta Y,
and delta Z (in Earth-Centered Cartesian coordinates); and by delta north, delta
east, and delta up (in local plane coordinates).
control point / control
station
A monumented point to which coordinates have been, or are being, assigned by
the use of surveying observations.
coordinate system
A mathematically defined method for specifying the locations of points. Distances
or angles from suitable references located the points within the system.
coordinates
A set of numbers used in specifying the location of a point.
correction
Changes to the measured slope distance or vertical angle to correct for
atmospheric conditions and the curvature of the earth.